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Topic Review
Blastula
The blastula (from Greek βλαστός (blastos), meaning "sprout") is a hollow sphere of cells, referred to as blastomeres, surrounding an inner fluid-filled cavity called the blastocoel formed during an early stage of embryonic development in animals. Embryo development begins with a sperm fertilizing an egg to become a zygote which undergoes many cleavages to develop into a ball of cells called a morula. Only when the blastocoel is formed does the early embryo become a blastula. The blastula precedes the formation of the gastrula in which the germ layers of the embryo form. A common feature of a vertebrate blastula is that it consists of a layer of blastomeres, known as the blastoderm, which surrounds the blastocoel. In mammals the blastula is referred to as a blastocyst. The blastocyst contains an embryoblast (or inner cell mass) that will eventually give rise to the definitive structures of the fetus, and the trophoblast, which goes on to form the extra-embryonic tissues. During the blastula stage of development, a significant amount of activity occurs within the early embryo to establish cell polarity, cell specification, axis formation, and to regulate gene expression. In many animals such as Drosophila and Xenopus, the mid blastula transition (MBT) is a crucial step in development during which the maternal mRNA is degraded and control over development is passed to the embryo. Many of the interactions between blastomeres are dependent on cadherin expression, particularly E-cadherin in mammals and EP-cadherin in amphibians. The study of the blastula and of cell specification has many implications in stem cell research and assisted reproductive technology. In Xenopus, blastomeres behave as pluripotent stem cells which can migrate down several pathways, depending on cell signaling. By manipulating the cell signals during the blastula stage of development, various tissues can be formed. This potential can be instrumental in regenerative medicine for disease and injury cases. In vitro fertilisation involves implantation of a blastula into a mother's uterus. Blastula cell implantation could serve to eliminate infertility.
  • 1.4K
  • 30 Nov 2022
Topic Review
Lignocellulosic Biofuels: A Renewable Bioenergy
Biofuel consists of non-fossil fuel derived from the organic biomass of renewable resources, including plants, animals, microorganisms, and waste. Energy derived from biofuel is known as bioenergy. The reserve of fossil fuels is now limited and continuing to decrease, while at the same time demand for energy is increasing. In order to overcome this scarcity, it is vital for human beings to transfer their dependency on fossil fuels to alternative types of fuel, including biofuels, which are effective methods of fulfilling present and future demands. The conversion of lignocellulosic feedstock is an important step during biofuel production. It is, however, important to note that, as a result of various technical restrictions, biofuel production is not presently cost efficient, thus leading to the need for improvement in the methods employed. 
  • 1.4K
  • 26 Apr 2022
Biography
Gennady Zyuganov
Gennady Andreyevich Zyuganov (Russian: Генна́дий Андре́евич Зюга́нов; born 26 June 1944) is a Russia n communist politician who has been the leader of the Communist Party of the Russian Federation since 1993. He has been Chairman of the Union of Communist Parties - Communist Party of the Soviet Union (UCP-CPSU) since 2001, a deputy in the State Duma since 1993, and a m
  • 1.4K
  • 28 Nov 2022
Topic Review
Blood-Brain Barrier: Functionalised Chitosan
The major impediment to the delivery of therapeutics to the brain is the presence of the blood-brain barrier (BBB). The BBB allows for the entrance of essential nutrients while excluding harmful substances, including most therapeutic agents; hence, brain disorders, especially tumors, are very difficult to treat. Chitosan is a well-researched polymer that offers advantageous biological and chemical properties, such as mucoadhesion and ease of functionalization. Chitosan-based nanocarriers (CsNCs) establish ionic interactions with the endothelial cells, facilitating the crossing of drugs through the BBB by adsorptive mediated transcytosis. This process is further enhanced by modifications of the structure of chitosan, owing to the presence of reactive amino and hydroxyl groups. Finally, by permanently binding ligands or molecules, such as antibodies or lipids, CsNCs have shown a boosted passage through the BBB, in both in vivo and in vitro studies which will be discussed in this review.
  • 1.4K
  • 21 Nov 2020
Topic Review
Role of  Insects in Spread of  Foodborne Pathogens
Insects play a key role in European agroecosystems. Insects provide important ecosystem services and make a significant contribution to the food chain, sustainable agriculture, the farm-to-fork (F2F) strategy, and the European Green Deal. Edible insects are regarded as a sustainable alternative to livestock. 
  • 1.4K
  • 20 Feb 2023
Topic Review
Gluten-Free Bread and Bakery Products Technology
Gluten intolerance is becoming more common in the population, and patients with this intolerance must follow a gluten-free diet. Bread and other bakery products are staple foods and pose a problem in a gluten-free diet due to their short shelf life and the need to replace gluten. Naturally gluten-free cereals and pseudocereals, but also milled legumes, seeds and nuts, are being increasingly used for the preparation of gluten-free baked goods.
  • 1.4K
  • 25 Feb 2022
Topic Review
Helianthus Annuus
Helianthus annuus, the common sunflower, is a large annual forb of the genus Helianthus grown as a crop for its edible oil and edible fruits. This sunflower species is also used as wild bird food, as livestock forage (as a meal or a silage plant), in some industrial applications, and as an ornamental in domestic gardens. The plant was first domesticated in the Americas. Wild Helianthus annuus is a widely branched annual plant with many flower heads. The domestic sunflower, however, often possesses only a single large inflorescence (flower head) atop an unbranched stem. The name sunflower may derive from the flower's head's shape, which resembles the sun. Sunflower seeds were brought to Europe from the Americas in the 16th century, where, along with sunflower oil, they became a widespread cooking ingredient.
  • 1.4K
  • 19 Oct 2022
Topic Review
Biomechanical Factors in Track and Field Sprint Start
In athletics sprint events, the block start performance can be fundamental to the outcome of a race. Several biomechanical determinants of sprinters have been identified. In the “Set” position, an anthropometry-driven block setting facilitating the hip extension and a rear leg contribution should be encouraged. At the push-off, a rapid extension of both hips and greater force production seems to be important. After block exiting, shorter flight times and greater propulsive forces are the main features of best sprinters. 
  • 1.4K
  • 13 Apr 2022
Topic Review
Copper Complexes as Topoisomerases Inhibitors
Organometallics, such as copper compounds, are cancer chemotherapeutics used alone or in combination with other drugs. A group of copper complexes exerts an effective inhibitory action on topoisomerases, which participate in the regulation of DNA topology. Copper complexes of topoisomerase inhibitors work by different molecular mechanisms that have repercussions on the cell cycle checkpoints and death effectors. 
  • 1.4K
  • 14 Oct 2020
Topic Review
Seaweed Extracts
The use of seaweed-based bioproducts has been gaining momentum in crop production systems owing to their unique bioactive components and effects. They have phytostimulatory properties that result in increased plant growth and yield parameters in several important crop plants. They have phytoelicitor activity as their components evoke defense responses in plants that contribute to resistance to several pests, diseases, and abiotic stresses including drought, salinity, and cold. 
  • 1.4K
  • 01 Jul 2021
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